This application for a Mentored Patient-Oriented Research Career Development Award (K23) is a new submission by a new investigator. The candidate proposes a program of research and training with the following goals: 1) to gain expertise in the design and conduct of randomized clinical trials (e.g., research design, study administration, biostatistics) that will enhance the quality of her scientific work throughout her career;2) to deepen her understanding of the etiology and progression of cardiovascular disease, as well as the relationship of obesity and depression to incident cardiovascular disease (CVD) risk factors;3) to increase her understanding of the etiology and treatment of obesity and depression, and to develop skills to objectively assess a treatment that targets each disorder;and 4) to gain further training in the responsible conduct of research and ethical issues related specifically to patients with comorbid obesity and other disorders. This training will prepare the candidate to conduct a randomized controlled trial that will establish initial effect size, and feasibility, of a new treatment that concurrently targets obesity and depression. The intervention is designed to demonstrate that: 1) obese, depressed individuals can achieve clinically significant weight losses;and 2) that weight reduction is associated with favorable changes in CVD risk factors and mood. Obesity and depression are independent risk factors for incident CVD. Weight losses of moderate magnitude (e.g., ~5% of initial weight) been shown to improve risk factors for CVD, yet depressed individuals are routinely screened out of weight loss trials. This practice stems from concern that weight reduction may exacerbate symptoms of depression, despite the lack of empirical evidence to support this idea. Thus, it is unknown whether obese individuals with clinical depression can safely undertake weight reduction, and whether there are concomitant improvements in CVD risk factors. Participants (n = 50) who are both obese and depressed, with at least two risk factors for CVD, will be randomly assigned to group cognitive-behavioral therapy for the treatment of depression combined with behavior modification for weight loss (Combined Treatment), or to a combination of GCBT and a non-dieting approach to weight loss (GCBT-ND). We hypothesize that the Combined Treatment will concurrently induce weight loss, improve mood, and result in improvements in CVD risk factors in obese, depressed individuals. Persons receiving Combined Treatment are expected to lose significantly more weight than those in the GCBT-ND condition after 20 weeks of treatment. These participants are also expected to show greater improvements in CVD risk factors than those receiving GCBT-ND. Mood is expected to improve in both conditions, as all participants will receive group CBT for depression. The proposed study will be the first randomized controlled trial to assess whether weight loss and improvements in CVD risk factors can be effectively achieved in obese individuals with clinical depression. The research and training experiences described in this proposal will prepare the candidate for continued independent clinical research in the relationships of obesity and depression to cardiovascular disease.